To help inspire other data centers to be more energy efficient as well, Google has established a website (www.google.com/datacenters) that explains a number of its efficiency efforts, as well as how it calculates its PUE. Energy efficiency, of course, is a common goal in data centers. But in organizational structures where IT and facility management are separate, it can also lead to conflict. After all, while facility management is concerned about energy efficiency and the cost of energy, IT is more concerned about performance than efficiency. So, IT specifies equipment that maybe isn't as efficient as it could be, which leads to challenges for facilities when the CFO starts inquiring about the data center utility bill, which, according to a Building Operating Management survey, is paid by the facility department in 80 percent of organizations.

In Google's structure, IT ultimately reports to the person paying the utility bill, so energy efficiency becomes something that IT needs to keep a close eye on.

"You could go and talk to any of the IT guys in any of our data centers and they would be as keenly aware of PUE and energy consumption and availability of our servers as the facility operations teams are," says Kava.

That structure made it easier for Google to take a step most organizations wouldn't consider — overhauling the cooling and power equipment at its Oregon data center after less than seven years of operation. The upgrade was needed because the existing infrastructure didn't provide the needed "optionality" — Google-speak for flexibility — to enable Google to install more efficient servers.

"Many data center operators would consider that ridiculous, to consider ripping out the guts of the data center and replacing it after only six or seven years in operation," says Kava. "But for us, it made complete sense because the generation of servers that we wanted to deploy today would not be accommodated with the cooling and some of the power infrastructure that we had deployed back seven years ago. When you run the numbers, it made complete sense, on a total cost of ownership basis." Deploying all those new servers gave Google a tremendous increase in computing capacity at a much, much lower cost of operation, because the new servers are far more energy efficient than the old ones.